I installed System Works 2005 Premium edition a few years ago on a W98SE dektop from an original CD bought from PC World. It mostly worked fine, although I stopped using some troublesome featues.
At a couple of random times in the past it flashed up a message saying the product was not activated, and forced me to re-activate it, which always worked. However, today, I was clearing icons off my desktop and sending to wipe info. The first worked OK and then I got a pop-up saying the product wasn't activated. I tried the usual on-line activation, and got an error message saying the product key was invalid (which it wasn't). I rebooted and tried again. This time It appeared to go through the activation correctly, but when I clicked on the 'System Works' icon, got a message saying 'Trial Period Expired'. This was a full time-unlimited licence product, not a trial. After trying to avtivate a few more times, I got a new message saying the number of permitted installations had been exceeded, however, I have only ever installed this stuff on one PC, and also only once.
After contacting Customer Services (took over 2 hours before someone answered the phone) was told that the product key I gave him was invalid (said the new keys have 25 digits and mine had 24). Eventually he said he couldn't do anything and suggested I post a question on this forum. I wonder if anyone else has come across this problem, and found a solution. The product is only 8 years old, and even MS keep theirs going for 10 years. I'm not looking for upgrades, just to be able to use the product I have already paid for and been using for years.